An Orbital Sciences Corp. Antares rocket making only its fifth flight exploded seconds after launch from the Virginia coast Tuesday, erupting in a spectacular fireball and destroying an uncrewed Cygnus cargo ship in a disheartening failure for NASA’s commercial space station resupply program.

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"But I can assure you we will find out what went wrong and we will correct it and will fly again," Culbertson says.

"What we know so far is pretty much what everyone saw on the video. The ascent, there was some, let's say, disassembly of the first stage it looked like and the vehicle fell to Earth," said Frank Culbertson. "We don't have any early indications of what might have failed."

"Launch is a really tough business," said Bill Gerstenmaier, associate administrator of NASA's Human Exploration and Operations Mission Directorate.

Orbital will lead the investigation with the FAA and NASA.

The crew of the International Space Station is in no danger and there was no critical consumables lost in the mishap.

There were no injuries on the ground from the mishap, said Frank Culbertson, executive vice President and general manager of Advanced Programs Group at Orbital Sciences Corp.

The problem will be investigated and flights will resume, Culbertson said. The data is being looked at by investigators already. The crash scene will be opened to teams at daybreak.

If any of the local residents find any debris, they are urged to call 757-824-1295.

The post-failure news conference is scheduled for 8:30 p.m. EDT.

A gallery of photos from the failure is posted here.

A video of the ill-fated flight is posted here.

A post-failure news conference is not expected before 8 p.m. EDT (0000 GMT). Orbital Sciences is in the process of impounding the data and telemetry from tonight's launch for the investigation that will involved several government agencies. There were no injuries reported.

Contingency operations are in effect. Damage appears contained to the launch pad itself.

THE VEHICLE HAS EXPLODED AND FELL BACK ONTO THE PAD.

LIFTOFF of the Antares rocket with the "Deke Slayton" Cygnus cargo craft, resupplying the International Space Station with provisions and experiments.

T-minus 5 seconds. Transporter erector is swinging back. Standing by for ignition!

T-minus 15 seconds. The engine steering check is underway.

T-minus 60 seconds. High speed video cameras are activating.

T-minus 90 seconds.

T-minus 2 minutes. Flight computer is ready. The rocket's propellant tanks are pressurizing now.

In the next few moments, the Antares first stage's propellant tanks will pressurize for flight, and computers will monitor the rocket and ground system parameters to ensure everything is ready for liftoff.

At T-minus 15 seconds, the two AJ26 first stage engines will swivel at the base of the rocket to ensure they can steer the launch vehicle in flight.

At T-minus 5 seconds, the transporter-erector-launcher will retract away from the rocket, leading to ignition of the AJ26 engines as clocks hit zero.

Liftoff will occur 2 seconds later after computers verify the engines are running normally.

T-minus 3 minutes, 30 seconds. The auto sequence has started.

T-minus 4 minutes and counting. The automatic countdown sequence begins in a few seconds.

T-minus 5 minutes and counting. The rocket is now running on its own battery system.

T-minus 7 minutes and counting. The liquid oxygen tank is full. The transporter erector is armed for rapid retract in the final seconds of the countdowm.

T-minus 8 minute and counting. No problems are reported in the countdown and the weather continues to look favorable for liftoff at 6:22:38 p.m. EDT.

T-minus 10 minutes and counting. The next step in the engine chilldown procedure is now beginning. And final vehicle arming is underway.

T-minus 11 minutes and counting. The final prelaunch poll of the Antares team confirms all positions are ready for the final phase of the countdown.

T-minus 13 minutes and counting. The roughly five-ton Cygnus spacecraft, christened the "Deke Slayton" after the Mercury Seven astronaut, is running on internal power and is in good shape for launch.

The Cygnus spacecraft will reach the International Space Station on Nov. 2 after launch tonight.

T-minus 16 minutes and counting. Another poll is coming up at T-minus 12 minutes to approve the start of a medium-flow chilldown, another step to condition the main engines for ignition.

The Antares launch team continues stepping through countdown procedures toward liftoff at 6:22:38 p.m. EDT (2222:38 GMT).

Upper level winds are reported favorable for launch.

T-minus 20 minutes and counting.

Today's launch will fly southeast from Wallops Island, Va. Communications sites in Virginia, North Carolina and Bermuda will track the rocket during its 10-minute flight, along with support from NASA's Tracking and Data Relay Satellite System.

Check out a timeline of key events during the launch.